1. Field of the Invention
The present invention relates to a fuel/air mixing device particularly suited for mixing producer gas with air to fire an internal combustion engine.
2. Description of the Prior Art
Petroleum shortages and its high cost are helping destroy the hard won economic gains of the developing countries. This growing dilemma over petroleum provides the incentive to investigate alternative fuels, especially those suited for direct use in existing engines and machines. One of the alternative fuels which is receiving recognition and gaining prime importance for research and development and application is producer gas. This gas is a product of gasification which thermally converts solid fuel into a combustible gas.
Producer gas technology is not a new development. It was used in blast furnaces about two centuries ago and was developed and used in Europe and Asia to run cars, tractors, and trucks during World War II. An early system for providing an air and gas mixture to fire an internal combustion engine is disclosed in U.S. Pat. No. 986,754, issued to O. Podhajsky on Mar. 14, 1911. The use of producer gas was rapidly discarded after World War II as low cost petroleum-based energy became readily available.
Recent shortages and the rapidly escalating cost of petroleum products have renewed interest in gasification as a potential economic source of energy. To reduce the dependency on imported petroleum, it is desirable to be able to use producer gas generated from bio-mass, such as wood, straw, husk from rice, and other cereal crops, tree groomings and other agricultural residues and energy crops to run engines for the agricultural industry and other energy needs.
At present, gasification research and development has taken two major routes, one of which is the development of small scale, technological simple down draft designs for use in developing countries. The other is the large scale automated and continuous feed systems for developed or industrialized nations. The present invention was specifically designed for use with producer gas generated by the small scale, down draft designs for use in remote areas, although it is equally well suited for other types of producer gas generators. In particular, the present invention permits operation of an internal combustion engine with a low pressure fuel source. The flow of fuel is maximized while the flow of air can be selectively controlled to control the air/fuel mix. The system is readily adapted to existing carburetor engines without altering the carburetor or standard throttle system.